Epigenetic Patterns and Geographical Parthenogenesis in the Alpine Plant Species (Ranunculaceae).

Polyploidization and the shift to apomictic reproduction are connected to changes in DNA cytosine-methylation. Cytosine-methylation is further sensitive to environmental conditions. We, therefore, hypothesize that DNA methylation patterns would differentiate within species with geographical parthenogenesis, i.

Effects of cold treatments on fitness and mode of reproduction in the diploid and polyploid alpine plant Ranunculus kuepferi (Ranunculaceae).

Background And Aims: Alpine plants grow in harsh environments and are thought to face occasional frost during the sensitive reproductive phase. Apomixis (asexual reproduction via seed) can be advantageous when sexual reproduction is disturbed by cold stress. Apomictic polyploids tend to grow in colder climates than their sexual diploid relatives.

Reconstructing geographical parthenogenesis: effects of niche differentiation and reproductive mode on Holocene range expansion of an alpine plant.

Asexual taxa often have larger ranges than their sexual progenitors, particularly in areas affected by Pleistocene glaciations. The reasons given for this 'geographical parthenogenesis' are contentious, with expansion of the ecological niche or colonisation advantages of uniparental reproduction assumed most important in case of plants. Here, we parameterized a spread model for the alpine buttercup Ranunculus kuepferi and reconstructed the joint Holocene range expansion of its sexual and apomictic cytotype across the European Alps under different simulation settings.

Pathways to polyploidy: indications of a female triploid bridge in the alpine species (Ranunculaceae).

Polyploidy is one of the most important evolutionary processes in plants. In natural populations, polyploids usually emerge from unreduced gametes which either fuse with reduced ones, resulting in triploid offspring (triploid bridge), or with other unreduced gametes, resulting in tetraploid embryos. The frequencies of these two pathways, and male versus female gamete contributions, however, are largely unexplored.

Correlations of polyploidy and apomixis with elevation and associated environmental gradients in an alpine plant.

Apomictic plants expand their geographical distributions more to higher elevations compared to their sexual progenitors. It was so far unclear whether this tendency is related to mode of reproduction itself or represents a side effect of polyploidy. Apomixis is advantageous for range expansions as no mating partners and pollinators are needed (Baker's rule).

A matter of scale: apparent niche differentiation of diploid and tetraploid plants may depend on extent and grain of analysis.

Aim: Emerging polyploids may depend on environmental niche shifts for successful establishment. Using the alpine plant as a model system, we explore the niche shift hypothesis at different spatial resolutions and in contrasting parts of the species range.

Location: European Alps.

Niche dynamics of alien species do not differ among sexual and apomictic flowering plants.

Biological invasions can be associated with shifts of the species' climatic niches but the incidence of such shifts is under debate. The reproductive system might be a key factor controlling such shifts because it influences a species' evolutionary flexibility. However, the link between reproductive systems and niche dynamics in plant invasions has been little studied so far.

Sustainable diversity. This year's Top 25 minority Executives in Healthcare highlights leadership diversity, but some question the true level of inclusion.

While more minority candidates are moving into top healthcare positions, many challenges remain. One is to address true inclusion, an expert says. And Andrea Price, left, selected as one of Modem Healthcare's Top 25 Minority Executives in Healthcare, says minorities can have a hard time rising to top positions.

A woman's place is in...healthcare, as Modern Healthcare's Top 25 Women connote explosive growth in the number of female executives in C-suites.

More women are moving into C-suites across the healthcare industry, and this year's Top 25 Women in Healthcare represent some of the highest-profile females to make the move. Angela Braly, shown center, with co-workers, becomes the first woman CEO of WellPoint in June, and says the trend will soon be a nonstory, "because there are going to be so many women leaders in healthcare".